ABSTRACT
BACKGROUND: Influenza is a leading cause of morbidity and mortality globally. Little is known of the true burden and epidemiology of influenza in Africa. Nigeria has a sentinel surveillance system for influenza virus (IFV). This study seeks to describe the epidemiological characteristics of influenza cases in Nigeria through secondary data analysis of the sentinel surveillance data from 2010 to 2020. METHODOLOGY: A retrospective secondary data analysis of data collected from patients with influenza-like illness (ILI) and severe acute respiratory infection (SARI) in the four Nigeria Influenza Sentinel Surveillance sites from January 2010 to December 2020. Data was cleaned and analyzed using Microsoft Excel and Epi info 7.2 for frequencies and proportions. The results of the analysis were summarized in tables and charts. RESULTS: A total of 13,828 suspected cases of influenza were recorded at the sentinel sites during the study period. About 10.3% (1421/13,828) of these tested positive for IFV of which 1243 (87.5%) were ILI patients, 175 (12.3%) SARI patients, and 3 (0.2%) novel H1N1 patients. Males accounted for 54.2% (770/1421) of the confirmed cases. The median age of confirmed cases was 3 years (range: <1month-97 years). Children 0-4 years accounted for 69.3% (985/1421) of all cases. The predominant subtypes were B lineage not determined (32.3%), A/H1N1 pdm09 (28.8%) and A/H3 (23.0%). There were periods of sustained transmission in most years with 2011 having the highest number of cases. Overall, there were more cases around January to March and August to November. Heart disease and chronic shortness of breath were the most common co-morbidities identified among confirmed cases. CONCLUSION: Influenza remains a significant cause of respiratory illness, especially among children aged less than 4 years. Influenza cases occur all year round with irregular seasonality in Nigeria. Children less than 4 years and those with co-morbidities should be prioritized for vaccination. Vaccine composition in the country should take cognizance of the prevailing strains which are type B (lineage not determined), A/H1N1 pdm09 and A/H3.
Subject(s)
Influenza A Virus, H1N1 Subtype , Influenza Vaccines , Influenza, Human , Child , Male , Humans , Infant , Influenza, Human/epidemiology , Nigeria/epidemiology , Sentinel Surveillance , Retrospective Studies , SeasonsABSTRACT
Background: Children living with HIV (CLWH) are at risk of colonisation and infection with meticillin-resistant Staphylococcus aureus (MRSA). All S. aureus isolates from CLWH with bloodstream infections in Kano were MRSA. Aim: To estimate the prevalence of nasal colonisation with S. aureus and MRSA in CLWH in Kano State and to determine associated risk factors. Methods: A cross-sectional study was performed in the infectious diseases clinics of two public hospitals in Kano involving 214 CLWH/caregiver pairs. Children were selected from clinic registers by simple random sampling and an interviewer-administered questionnaire used to elicit factors associated with MRSA carriage from the caregivers. Clinical records were reviewed for patients' medical histories. Standard laboratory techniques were used to isolate S. aureus from nasal swabs collected from CLWH. MRSA was detected using the cefoxitin disc diffusion method and PCR for mecA gene detection. We measured the prevalence of S. aureus and MRSA carriage in the CLWH and calculated adjusted odds ratios (AOR) for factors associated with MRSA. Results: Nasal S. aureus carriage in CLWH was 18.7% (40/214). Cefoxitin disc diffusion identified 6/214 (2.8%) of CLWH were MRSA carriers, while PCR identified that 9/214 (4.2%) of CLWH were MRSA carriers. Recent hospitalisation (AOR: 61.04; 95% CI: 9.01-413.38) and recent antibiotic therapy (AOR: 7.52; 95% CI: 1.07-52.95) were independent risk factors for MRSA colonisation. Conclusions: The rate of MRSA nasal colonisation among CLWH in Kano was similar to that reported in other studies in Africa. Infection prevention and control measures including MRSA screening and decolonisation, as well as education for CLWH and their carers should be introduced to reduce MRSA spread.
